Opinions on Worn Tire

[mikerueve]

Please look at the attached picture. It is of the tire that I finally removed from our teardrop near the end of our Route 66 trip. The tire had approximately 4500 miles on it at the time I swapped it out. It was part of the set that was shipped with the original Northern Tool trailer. It was on the passenger side of the trailer. The tire on the driver's side survived the entire trip with tread remaining (it has roughly 6500 miles on it now). These tires are 12 inch, 5.3 width. The tires were inflated to 60 psi. I think they are rated for 80 psi. There doesn't appear to be any pronounced camber on either side of the trailer that I can see. The trailer tows straight and there is no fish-tailing that I noticed. I was careful to evenly load the items that were carried in the trailer. If anything there would have been a slight bias toward the Driver's side due to the positioning of my battery.

During our trip, the vast majority of our time was spent on the original alignments of Route 66(whenever we could find it). The old two-lane roads do have more of a pronounced crown than modern roads. I'm wondering if this could have contributed to this type of wear. By this I mean the trailer "leaning" more to the outside, or passenger, side. The only thing that makes me dubious of this is the fact that there appears to be tread left at the very outside of the tire.

Anyways, take a look and let me know what you think. Should I look at getting a "better" quality trailer tire? If so, what are your reccomendations? Also, I'm considering going to a 13 inch wheel/tire setup. It seems that a lot of people are of the opinion that you can get a higher quality trailer tire in that size. Is it worth it?

Thanks in advance for any help.

[absolutsnwbrdr]

Getting a better quality tire is always a good thing, but from the wear pattern it looks like your tire was overinflated for the weight of the trailer. I'd drop at least 5-10psi and give it a go. Its hard to tell which side of the tire was facing in and out, but the off-center wear pattern is either due to the slight camber of the axle, or the axle stub could be slightly bent. I wouldn't be too concerned with that. But definitely lose some air.

On my first two trailers (HF with 5.30x12) I ran around 45psi. The trailer probably weighed around 1500lbs when loaded. Highway speeds were never a problem (usually cruised at 65-70mph), and the reduced psi gave the trailer a little more cushion over the bumps.

[mikerueve]

Yeah, I suspected over-inflation myself. (At least that's what I hoped it was)

[KCStudly]

Over inflation was my first thought, too, but it doesn't seem to me that there would be that drastic of a difference side to side with only a battery's weight difference. On the other hand, if we consider the possibility that a spindle is slightly out of alignment: 1) up-down/camber I would expect the wear to show on the inside or outside more, or 2) toe in-toe out I would expect the scrub forces to make the trailer crab and equalize the wear between the tires. So, by my logic (which is probably missing something) neither issue fully explains the condition.

I am assuming that the wear is fairly even all around the tire and that there is no scalloping, cupping or scrubbing apparent.

How certain or you that the load was relatively evenly distributed?

Did the tire temperatures seem the same on both sides right after stopping?

One technique to determine proper tire inflation is to rub chalk across the tread, roll the trailer in a straight line on flat pavement and see that the chalk wears off evenly (while staying within the tire mfg's recommendations). Max psi at max load is just that and should not necessarily be taken as the defacto pressure setting.

[KCStudly]

... on the other hand, I suppose it is possible that the weight of the battery being offset could bias a crabbing/scrubbing scenario onto the lighter side, and thus cause an imbalance in wear. Schmaybe.

Leaf springs would be more susceptible to this because compression of the spring changes its relative length. Squish one spring more than the other and it changes the alignment of the axle under the trailer. In theory, at least.

[angib]

It's curious how often folk say trailer tires should be inflated to the maximum on the sidewall, but they never say the same about other vehicle tires.

I think this looks like a case of 'gross' overinflation but then 4500 miles on a tire seems awful short, so maybe there was some other effect at work (like poor tire quality).

As a broad rule of thumb, reduce the pressure from the maximum by the same amount that the actual load is below the maximum load - three-quarter pressure for three-quarter load, half pressure for half load, etc.

[mikerueve]

Thanks for all of the thoughtful responses. Both tires were inflated to approximately the same psi. I did inspect the tires and bearings for unusual heat at almost every fill up. Nothing seemed irregular to my touch anyways. I'm hoping that what I've learned is a lesson on over-inflation. It was a "bumpy ride" at times. Like I said, the trailer tracked well, and there was no noticeable crabbing.

[Socal Tom]

One technique to try is to load the trailer, then apply chalk across the face of the tire and roll forward a few revolutions and you should see even removal of the chalk, if you don't, lower the pressure.

Tom

[citylights]

Looks like light weight teardrop for rating of tire, over inflated tire for the load, then axle camber pushing the wear to the outside track.

I would get a better quality tire and reduce the pressure some. Your option on going with a bigger tire. (I did.)

[eamarquardt]

One thing that is overlooked with trailers is the potential need for a real alignment. See:

http://www.thisoldcampsite.com/This_old ... gnmen.html

I think that there's more going on with the wear you're seeing than simple over inflation.

I imagine a frame straightening shop, versus a simple alignment shop, would be able to measure, align, and tweak your axle as required.

Hope this helps.

Cheers,

Gus

[citylights]

One thing that is overlooked with trailers is the potential need for a real alignment.
Gus

Trailer alignment is not as complex as car alignment. Axle installation directions call for a simple measurement from end of spindal to center of coupler. They give a centimeter or so allowable slop. There is no camber adjustment for the tires. Surprisingly simple, but it is because the three points define the towing plane.

If you are worried about it being out of alignment, just do the measurement and see how far off it comes out.

[eamarquardt]

One thing that is overlooked with trailers is the potential need for a real alignment.
Gus

Trailer alignment is not as complex as car alignment. Axle installation directions call for a simple measurement from end of spindal to center of coupler. They give a centimeter or so allowable slop. There is no camber adjustment for the tires. Surprisingly simple, but it is because the three points define the towing plane.

If you are worried about it being out of alignment, just do the measurement and see how far off it comes out.

Citylights, I disagree. You don't have caster with fixed trailer axles but you certainly toe in/toe out and camber. If he's having problems and eating up a tire in 4500 miles there is a problem. I'm confident a good frame shop could sort it out and tweak the axle or installation to rectify the problem. It could be that a spindle wasn't welded on correctly and even though the "spindal to center of coupler" distances are equal something could be wrong.

I suggest you read the article I referenced. It's pretty specific and enlightening.

http://www.thisoldcampsite.com/This_old ... gnmen.html

Cheers,

Gus

[48Rob]

One of the most common causes for trailer tire wear in my experience is a bent axle.

Doesn't take a lot hitting a big pothole at speed to throw it out.
The axle doesn't always bend up, it usually bends back slightly.
The tire in the picture does look overinflated, and if the axle/spindle was bend slightly back, it would scrub the center of the tire.
Wouldn't hurt to check the wheels too, a bent wheel combined with overinflation will scrub the rubber off fast too.

Rob

[citylights]

I suggest you read the article I referenced. It's pretty specific and enlightening.
http://www.thisoldcampsite.com/This_old ... gnmen.html

Ok, that was a good read. The axle could be bent. It is worth taking the measurements to check it out.

[KCStudly]

I'm with Gus on this one. If only one tire is wearing, all other things being equal, it can not be blamed on over inflation. Equalizing the tip to tip measurement of the axle stubs to the coupler at time of axle installation presumes that the axle was correct to begin with and has not changed due to road hazard or other mishandling.

Something as simple as welding the spring perches on with the axle camber clocked (inducing caster) or welding the perches on out of phase (not level, or in the same plane with each other) could be contributing factors; although I admit that these factors should be fairly forgiving in most situations. It could be a combination of things.